The invention relates to endoscopes, and in particular, endoscopes that have imaging probes. Endoscopes are widely used to inspect regions of the body (e.g., cavities, joints) during surgery (such as laparoscopic/thoracoscopic surgery) through a small puncture. Typically, the endoscope includes an elongated insertion tube equipped with a set of optical fibers that extend from a proximal handle through the insertion tube to the distal viewing tip of the endoscope. An external light source provides light to the optical fibers via a cable that rigidly attaches to the handle (e.g., at a post on the side of the handle) of the endoscope.
An optical image of the target is collected by one or more lenses mounted in the distal viewing tip of the endoscope and is passed to, e.g., a solid-state image detector (such as a charge-coupled-device (CCD)). The CCD converts the received optical image to electrical signals that are processed for viewing on a display.
Some endoscopes have a direction of view (i.e., the direction along which the endoscope emits and receives light) along the longitudinal axis of the insertion tube. The distal viewing ends of other endoscopes are constructed to provide an off-axis direction of view (e.g., at 30 degrees or at 70 degrees).